The present invention relates to a silicone grease composition or, more particularly, to a grease composition comprising an organopolysiloxane as the base ingredient and capable of imparting dragging movability to the surfaces of bodies contacting with each other in a relative movement.
When surfaces of bodies contact each other with relative movement, such as in the shaft and bearing of a rotary-type variable resistor in an audio set, eject damper and pick-up damper in a cassette deck and the like it is often the practice to impart dragging movability thereto. The grease compositions currently used for such purpose include those comprising an organopolysiloxane as the base ingredient and those comprising a polybutene as the ingredient. In particular, Japanese Patent Publication No. 53-776 discloses a silicone grease composition comprising a dimethylpolysiloxane of a linear-chain molecular structure and an organopolysiloxane composed of monofunctional siloxane units R.sup.1.sub.3 SiO.sub.0.5, difunctional siloxane units R.sup.2.sub.2 SiO and tetrafunctional siloxane units SiO.sub.2, in which R.sup.1 and R.sup.2 are each a monovalent hydrocarbon group, as the organopolysiloxane component with admixture of a thickener and Japanese Patent Kokai No. 56-897 discloses a grease composition comprising an organopolysiloxane and a polybutene as the base oil component with admixture of sodium n-octadecyl terephthalamate and finely divided silicon dioxide filler. These grease compositions in the prior art are, however, not quite satisfactory in respect of the performance at low temperatures and have a disadvantage of poor stability that the movement time is gradually shortened when they are worked repeatedly.